Seminar by Assoc. Prof. Dr. La Duc Duong, Assoc. Prof. Dr. Tran Phan Thuy Linh and Dr. Lai Van Duy

On July 5, 2024, the lectures from Assoc. Prof. Dr. La Duc Duong, Assoc. Prof. Dr. Tran Phan Thuy Linh and Dr. Lai Van Duy  takes place in the meeting Room C

Assoc. Prof. Dr. La Duc Duong presents about "Fabrication of CuFe2O4/porphyrin nanocomposite via self-assembly approach as a photoanode for enhanced photoelectrochemical water splitting"

Abstract:

There has been considerable interest in generating self-assembled porphyrin nanostructures and their structured arrangements, driven by the goal of emulating natural light harvesting processes and energy storage mechanisms. Furthermore, this endeavor aims to pioneer new nanostructured materials for applications in photocatalytic processes such as photoelectrochemical water splitting. The fabrication of a CuFe2O4/porphyrin nanocomposite through a self-assembly approach is explored in this study, aiming to develop an efficient photoanode for enhancing the photoelectrochemical water splitting process. By combining the unique properties of CuFe2O4 and porphyrin nanostructures, the resulting nanocomposite demonstrates enhanced charge separation and improved light absorption, leading to heightened photoelectrochemical performance. The self-assembly method ensures the successful integration of the nanocomposite, creating a well-organized and synergistic structure. Experimental analyses, including techniques such as SEM, XRD, EDX, UV-vis, and photocurrent measurements, validate the successful formation of the nanocomposite and its noteworthy improvement in photoelectrochemical efficiency. This work presents a promising avenue for advancing photoelectrochemical water splitting through innovative material assembly strategies, contributing to the development of sustainable energy technologies..

Assoc. Prof. Dr. Tran Phan Thuy Linh presents about " 2D janus quintuple-layer atomic structures xcrsin2 XCrSiN2 (X= S, Se and Te): a first-principles study"

Abstract: 

By utilizing first-principles calculation based on Density  Functional Theory, the crystal structure, electronic properties and carrier mobility of the proposed 2D Janus XCrSiN2 (X=S, Se and Te) are investigated. The results show that these Janus structures XCrSiN2 (X=S, Se and Te) are energetically and thermally stable. The electronic properties analysis indicates that the proposed systems are semiconductors with small indirect band gap. By applying the biaxial strain, the electronic structures are modulated considerably. The transport properties of the proposed configurations are calculated and analyzed systematically, indicating the highly directional isotropy. Our results suggest that the proposed Janus XCrSiN2 could be potential candidates for various applications, especially in nanoscale electronic devices.

Dr. Lai Van Duy presents about "Enhanced Photocatalytic Performance of ZnO Nanoparticles Functionalized with 5-(4’-Carboxyphenyl)-10,15,20-Triphenylporphyrin-Zinc"

Abstract:

In this study, ZnO nanoparticles were decorated with 5-(4’-carboxyphenyl)-10,15,20-triphenyl porphyrin-zinc (ZnTPPCO2Na) and used for photocatalytic removal of Rhodamine B dye. ZnO nanoparticles were hydrothermally synthesized and then subjected to heat treatment, and finally coated with a thin layer of ZnTPPCO2Na derivatives in solution. The resulting ZnTPPCO2Na/ZnO composite was characterized using scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), UV–visible absorption spectroscopy (UV-vis), and Fourier transform infrared spectroscopy (FTIR). ZnO nanomaterials, initially homogeneous and pure, form clusters with rough spherical shapes of significantly larger diameter when unannealed compared to those annealed at 600°C. The morphology of ZnTPPCO2Na-coated ZnO remains nearly unchanged as the low amount of ZnTPPCO2Na forms an extremely thin layer on the surface of the ZnO nanoparticles. The composite exhibited promising photocatalytic activity in the degradation of Rhodamine B (RhB) in aqueous solution, outperforming pure ZnO-based nanoparticles. The synergistic combination of ZnO nanoparticles and ZnTPPCO2Na showed significantly enhanced photocatalytic performance, achieving an impressive 97.65% removal rate of RhB after 120 minutes of UV light irradiation. The photocatalytic mechanism of the ZnTPPCO2Na/ZnO composite, mainly involving •O2− and OH•, improves charge separation via exciton-coupled charge-transfer processes, showing promise for efficient degradation of RhB dye in environmental remediation applications.